Pre-senescence removal of asparagus (Asparagus officinalis L.) fern

Experiments were established to determine the effects of asparagus fern removal prior to senescence on subsequent crop yields, for the purpose of reducing soil surface residues with inoculum of Stemphyllium vesicarium. Fern was cut and removed in late September and in early October over four years. Control fern was left standing as is the standard commercial practice. Periodic measurements of net assimilation rates were made on whole plants of eight genotypes in separate plantings to determine the drop in photosynthetic rates from late July through late September. Assimilation rates dropped significantly after mid-September. Early removal of fern resulted in substantial risk of low yields in subsequent years, whereas late removal of fern did not result in significant yield reductions as compared to the control.